Wideband Doherty power amplifier using suitable peaking output matching network

Abstract

In this paper, a wideband Doherty power amplifier along with a novel design strategy for peaking output matching network is presented. The proposed matching network is designed by maintaining a predetermined electrical length to eliminate the using of peaking offset line for expanding the bandwidth effectively and improving the back-off efficiency. For higher than 50% efficiency at 6 dB back-off power, the proposed 2.3–2.8 GHz Doherty power amplifier can achieve nearly 20% relative operation bandwidth. For a 100 MHz wideband modulation signal, the efficiency of 49% and good linearity of −49 dBc can be achieved at about 9 dB back-off power after linearization.